During WWI pretty German master spy Helene von Lorbeer is sent undercover to London to live with the family of a high-placed British official where she is to rendezvous with the butler Valdar, also a spy, and help him transmit secret war plans back to Germany.
Acting
Karloff's butler villainy—subtle menace in every poured drink.
Cinematography
Shadowy staircases and gaslit paranoia on a B-movie budget.
Production
Warner Bros. wartime efficiency: entire espionage epic in an hour.

Director
Terry O. Morse
Trivia, insights & behind the scenes
Released as WWII loomed, this WWI spy tale functioned as thinly-veiled anti-German propaganda. Karloff's casting—a British actor playing villainous Germans—added meta-layers to the 'enemy within' paranoia.
This was a remake of 1930's 'Three Faces East,' itself based on a 1918 play—making this triple-dipped spy material that somehow still clocks shorter than most modern trailers.